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Victor Jrs. on 331 or 408: What are your dyno numbers?

  • Thread starter Thread starter slvr302
  • Start date Start date Nov 4, 2004

slvr302

Founding Member
May 10, 2002
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Nov 4, 2004
#1
  • Nov 4, 2004
  • #1
Looking for dyno numbers for guys running a 331 or 408 from out of box (untouched) Victor Jr. heads.
 

5.0 HOtrain

Founding Member
May 20, 2001
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Nov 4, 2004
#2
  • Nov 4, 2004
  • #2
I answered you're question on the corral, but with TFS "R" heads wich are maybe $150-$200 on my 418 are out of the box on pump gas made the #'s in the sig.
mike.
 

N8Miller

I need NOS....make it 2 of the big ones
Founding Member
Jul 26, 2000
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Nov 5, 2004
#3
  • Nov 5, 2004
  • #3
the vic jrs will make prolly close to 400 rwhp out the box. that is with all of the right things like cam, meter, injectors, blah blah blah
 

Rick 91GT

Mustang Master
Nov 29, 1999
9,692
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99
PA
Nov 5, 2004
#4
  • Nov 5, 2004
  • #4
You should have no problem making 500RWHP with them on a well built 408, with a good matched combo.

On the 331, 400RWHP can be had but the set-up gets a little wild and components have to be matched perfect. That peak numbner usually comes high in the rpm range.

We really need to know if this is a street car on pump gas, or a weekend warrior/race car that uses race gas? Hyd or soild roller? Auto or Manual? EFI or Carb? Rpm Range desired? What your goals are. This will greatly effect power output..
 

N8Miller

I need NOS....make it 2 of the big ones
Founding Member
Jul 26, 2000
2,661
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Kingston, PA, USA
Nov 5, 2004
#5
  • Nov 5, 2004
  • #5
slvr, im still debating on getting the heads. i replied on corral also.....

its them or afr 185s.
 

slvr302

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May 10, 2002
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Nov 5, 2004
#6
  • Nov 5, 2004
  • #6
Rick 91GT said:
You should have no problem making 500RWHP with them on a well built 408, with a good matched combo.

On the 331, 400RWHP can be had but the set-up gets a little wild and components have to be matched perfect. That peak numbner usually comes high in the rpm range.

We really need to know if this is a street car on pump gas, or a weekend warrior/race car that uses race gas? Hyd or soild roller? Auto or Manual? EFI or Carb? Rpm Range desired? What your goals are. This will greatly effect power output..
Click to expand...

Glad you asked. Here's what I have and looking for.

Car is a street car and will run on pump gas.
Hydraulic roller
5 SPD with EFI
3:73 gears
2000 rpms - 6500 rpms

I was going to build a 408 with 8.5 - 8.7 static compression.
I have an S-Trim from my old combo.

I am looking for 600 rwhp/600 rwtq and dont want to spin the crap out of the blower.
 

5.0 HOtrain

Founding Member
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Nov 5, 2004
#7
  • Nov 5, 2004
  • #7
I'm no blower expert, but wouldnt an "S" trim be a little small for a 408 with high flowing heads??
mike.
 

slvr302

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#8
  • Nov 5, 2004
  • #8
5.0 HOtrain said:
I'm no blower expert, but wouldnt an "S" trim be a little small for a 408 with high flowing heads??
mike.
Click to expand...

I think the S-trim may be too small but before I go for an upgrade, I'd bolt it on first to see if I can't achieve my 600rhwp/600rwtq goal. If not I'd upgrade to a T-trim
 

Rick 91GT

Mustang Master
Nov 29, 1999
9,692
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99
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Nov 5, 2004
#9
  • Nov 5, 2004
  • #9
slvr302 said:
I think the S-trim may be too small but before I go for an upgrade, I'd bolt it on first to see if I can't achieve my 600rhwp/600rwtq goal. If not I'd upgrade to a T-trim
Click to expand...

A power adder totally changes everything, since you are just forcing air into the runners.

I would want the head with the larger ports (runner cc), personally on a 408 I would go AFR225 or another comparable head. I would go YS-Trim as well, the T-trim seems to be peaky and they like to spin from what I know.

600hp should not be that hard to obtain....

NOW if it is a 331 the S-trim would be better suited but I think a larger blower would not stress as much..

I have a 358ci motor, worked AFR225's, ATI F1R air/water and plan to make 1200RWHP+.
 
9

93cobrastock

New Member
Oct 25, 2004
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Nov 5, 2004
#10
  • Nov 5, 2004
  • #10
i have a 408 and im expecting 900 rwhp no problem with 11lbs of boost @ 1600 CFM, i think your S trim setup will work fine for 600 wrhp. i run vic. jrs. ported, solid roller cam .514/.521. vic. jrs. are rated for 545hp on 351 CI engine.
 

slvr302

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Nov 10, 2004
#11
  • Nov 10, 2004
  • #11
Where is the cheapest place to get the AFR 225 and do they require anything special for the headers to bolt up?
 
S

SmockDoiley

New Member
Jun 14, 2003
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Nov 10, 2004
#12
  • Nov 10, 2004
  • #12
dude, I made 516/570 at only 4900 on a pump gas Twisted Wedge headed 342. If you cant make 600 at the wheels with a 408 and big heads you have a problem. A blown 331 with AFR 185s would be an excellent combo that would get you 600. If your just looking to make the most power but be streetable then I would go with the Vic Jr headed 408. The Vics are a 210 intake runner so slightly larger than AFR 205s but not too big to kill street manners. They are also like $600-700 cheaper. If your going to use it for the street then a huge head wouldnt do especially since your goals can be bet with a smaller head.
 
B

blackcloud50

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Mar 30, 2005
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Jun 18, 2006
#13
  • Jun 18, 2006
  • #13
SmockDoiley said:
dude, I made 516/570 at only 4900 on a pump gas Twisted Wedge headed 342. If you cant make 600 at the wheels with a 408 and big heads you have a problem. A blown 331 with AFR 185s would be an excellent combo that would get you 600. If your just looking to make the most power but be streetable then I would go with the Vic Jr headed 408. The Vics are a 210 intake runner so slightly larger than AFR 205s but not too big to kill street manners. They are also like $600-700 cheaper. If your going to use it for the street then a huge head wouldnt do especially since your goals can be bet with a smaller head.
Click to expand...

That 516/570 was at the rear wheels? What was the rest of the combo? Are you suggesting that the AFR 225 on a 408 won't have good street manners?
 

sunil6784

Member
Mar 31, 2005
620
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Boston, MA
Jun 18, 2006
#14
  • Jun 18, 2006
  • #14
SmockDoiley said:
dude, I made 516/570 at only 4900 on a pump gas Twisted Wedge headed 342. If you cant make 600 at the wheels with a 408 and big heads you have a problem. A blown 331 with AFR 185s would be an excellent combo that would get you 600. If your just looking to make the most power but be streetable then I would go with the Vic Jr headed 408. The Vics are a 210 intake runner so slightly larger than AFR 205s but not too big to kill street manners. They are also like $600-700 cheaper. If your going to use it for the street then a huge head wouldnt do especially since your goals can be bet with a smaller head.
Click to expand...


You got my attention. Whats the combo?
 

S&B

I hate my CT. :(
10 Year Member
Dec 18, 2005
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Cheesehead
Jun 18, 2006
#15
  • Jun 18, 2006
  • #15
my 331 made around 380 @ the wheels with the vic. jr's out of the box, with the vic. intake.

Now with my YSI it makes much more but that is a diff story
 
B

blackcloud50

New Member
Mar 30, 2005
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#16
  • Jun 19, 2006
  • #16
S&B said:
my 331 made around 380 @ the wheels with the vic. jr's out of the box, with the vic. intake.
Click to expand...

N/A? What was the rest of the combo and was this with a hydraulic roller?
 

S&B

I hate my CT. :(
10 Year Member
Dec 18, 2005
1,634
695
204
Cheesehead
Jun 19, 2006
#17
  • Jun 19, 2006
  • #17
OHh yeah sorry it was not hyd. roller. I really couldn't even tell you b/c so much has been done since then.
 
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